Cooperative Object Transportation Using Autonomous Networked Cobots: A Distributed Approach

This paper presents a cooperative object transportation method using a group of autonomous networked cobots (collaborative robots). The cobot featured in this study is equipped with an elbow manipulator with three revolute joints, a wrist, and an end-effector for object manipulation. Additionally, it is mounted on a mobile platform base, propelled by omnidirectional wheels. Two instances of such a robot are assigned the task of synchronously coordinating in real-time to transport a large, delicate object, such as a sheet of glass, from one place to another, thereby representing a realistic industrial application. The proposed solution consists of three subsystems, namely manipulator control, twin navigation, and distributed autonomy. The elbow manipulator mounted on each cobot is controlled using iterative inverse kinematic method based on dynamic analysis. The robot's path planning strategy employs a leader-follower formation and utilizes a feedback control scheme to accurately track the payload's position. The autonomy of the robot is distributed such that the actuator commands for each cobot are determined and executed locally on each cobot's onboard system. For our study, we designed a scenario within CoppeliaSim, a commercial robot simulator, to mirror realworld industrial settings. The performance of the proposed cooperative object transportation method is evaluated within the scenario, leveraging the support of multiple physics engine for a comprehensive evaluation.